You have several questions,
To answer the last one, yes... and no
On device's that use MTK CPU's, you don't need to unlock the bootloader as the bootloader on MTK's is not Fastboot . .MTK is famous for being UNBRICKABLE !!! Meaning you don't need to unlock the Fastboot at all...
The reason your having trouble is because it isn't necessary to unlock the bootloader ...
I'm not sure why Andy### thinks that being a MediaTek would make it harder, because that's just not the case... it usually means easier...
Let me explain why the Fastboot is useless..
On MediTek Device's, you dont flash new images via Fastboot because there is size limitations to each image, if you tried to flash a massive 3 GB system, it wouldn't allow you to, because of maximum flash size in Fastboot.... Instead MediaTek uses a Pre-Boot that is prior to the bootloader, it doesn't even have a GUI... This is called the Preloader on MTK Devices, and you do all your flashing using the Preloader... Usually you use a tool called SP Flash Tool for doing flashes....
Unlocking your bootloader isn't necessary, and disabling FRP is not going to make any changes to your bootloader unlocking... You flash a recovery image via the Preloader in SP Flash Tool, and then wipe the partition called FRP, and factory reset... it isn't like other Android ( HTC for example ) Htc devices need to be unlocked in order to install custom recoveries etc... this is not even a problem with MTK Device's because the Preloader gives you factory level flashing abilities.